CN109578801B

CN109578801B - Ultrahigh-pressure gas cylinder liner and manufacturing method thereof

Info

Publication number: CN109578801B
Application number: CN201811601588.0A
Authority: CN
Inventors: 王东坡; 马世成; 汪宇羿; 赵文龙; 张月倩; 孙昂
Original assignee: Aerospace Research Institute of Materials and Processing Technology
Current assignee: Aerospace Research Institute of Materials and Processing Technology
Priority date: 2018-12-26
Filing date: 2018-12-26
Publication date: 2020-07-10
Anticipated expiration: 2038-12-26
Also published as: CN109578801A

Abstract

The invention provides an ultrahigh-pressure gas cylinder liner and a manufacturing method thereof, wherein the gas cylinder liner is an integrated seamless-structure aluminum alloy liner with one end being sealed, the other end being closed to form a seal head and a bottle opening, the aluminum alloy liner comprises a bottom seal, a straight cylinder section, a seal head and a bottle opening, the bottom seal and the seal head are respectively positioned at two ends of the straight cylinder section, and the bottle opening is positioned on the seal head; the length of the aluminum alloy inner container is less than 5m, the nominal outer diameter of the straight cylinder section is phi 406-phi 850mm, and the rated pressure of the ultrahigh-pressure gas cylinder is 35-70 MPa. The invention adopts the plate blank as the raw material and adopts the spinning processing method, the whole product has no welding line, the preparation process is simple, the operation is convenient, the energy consumption is low, the pollution is small, and the loss of the raw material in the whole manufacturing process is less. The gas cylinder liner processed by the manufacturing method has the characteristics of high reliability, thin wall and light weight; the material structure in the gas cylinder is uniform and compact, the overall strength effect is excellent, and the gas cylinder has high pressure resistance and has important significance for manufacturing ultrahigh pressure gas cylinders.

Description

Ultrahigh-pressure gas cylinder liner and manufacturing method thereof

Technical Field

The invention belongs to the technical field of high-pressure containers, and particularly relates to an ultrahigh-pressure gas cylinder liner and a manufacturing method thereof.

Background

With the rapid development and industrialization of hydrogen fuel cells and electric vehicles, research and construction of hydrogen source technology and hydrogen energy infrastructure have attracted high attention in developed countries. The safe and economic hydrogen storage and transportation technology is the key point for pushing the hydrogen energy utilization to the practicability and industrialization. The most common and direct way of storing hydrogen is to use a super-high pressure gas cylinder with 35-70MPa of pressure to store hydrogen under high pressure. The high-pressure hydrogen storage can be used at normal temperature, the hydrogen can be directly released through the adjustment of the valve, the hydrogen storage cylinder has the advantages of simple structure, less energy consumption for preparing compressed hydrogen, high filling speed and the like, and the high-pressure hydrogen storage of the ultrahigh-pressure cylinder becomes a main mode of hydrogen energy storage and transportation at the present stage.

At present, the ultrahigh-pressure gas cylinder with the aluminum alloy liner and carbon fiber fully wound has a plurality of advantages, and the ultrahigh-pressure composite hydrogen cylinder with the aluminum alloy liner has the following advantages;

(1) the gas cylinder has light weight, good rigidity and high strength, the thickness of the material is only 50% -70% of that of the steel cylinder under the same performance, and the density is lower, so the weight of the gas cylinder is only 35% -40% of that of the traditional steel cylinder;

(2) the fatigue failure of the metal material is usually sudden failure without obvious warning, and the combination of a reinforcement in the composite material and a matrix can effectively transfer load and prevent the expansion of cracks, so that the fracture toughness of the gas cylinder is improved;

(3) when a large number of reinforcing fibers in the composite material cause the material to be overloaded and a few fibers to be broken, the load can be quickly redistributed to the fibers which are not damaged, so that the whole gas cylinder cannot lose the bearing capacity in a short time;

(4) when the composite material gas cylinder is damaged by impact or high-speed impact, dangerous fragments cannot be generated, so that the injury to personnel is reduced or avoided;

(5) the requirement of corrosion resistance can be met without special treatment;

(6) compared with the complex process required by a seamless steel gas cylinder, the fiber winding process is more flexible, easy to change, simpler in process, easy to realize automation and far lower in energy consumption than the production process of the steel gas cylinder;

(7) the fiber winding provides a convenient and reliable technical scheme for ultrahigh pressure, and is the most effective scheme for realizing 70MPa ultrahigh pressure hydrogen storage.

For example, the carbon fiber fully-wound gas cylinder with the aluminum alloy liner with the outer diameter of phi 406-phi 850mm and the length of not more than 5m is mainly used as a fuel gas cylinder of heavy trucks, medium-sized transport vehicles, buses, engineering vehicles and other types of vehicles, and a large-volume ultrahigh-pressure gas cylinder is used for mobile storage and transportation of modular hydrogen fuel gas cylinder sets and the like.

However, limited by material production and technical capability, China cannot produce the carbon fiber fully-wound ultrahigh-pressure gas cylinder with the aluminum alloy liner with the diameter larger than phi 406mm at present, and the core problem is that the aluminum alloy liner cannot be manufactured and mainly depends on import.

Under the above background, in order to further master the key technologies and products of large hydrogen storage and transportation devices with proprietary property rights, it is urgently needed to develop ultra-high pressure gas cylinder liner products with characteristics of large diameter, long length, light weight, high reliability and the like.

Disclosure of Invention

The invention aims to provide an ultrahigh-pressure gas cylinder liner and a manufacturing method thereof. At least solves the problems of small volume, overweight and poor reliability of the prior ultrahigh-pressure gas cylinder.

In order to achieve the above purpose, the invention provides the following technical scheme:

an ultrahigh-pressure gas cylinder liner is an aluminum alloy liner with an integrated seamless structure, wherein one end of the aluminum alloy liner is sealed, the other end of the aluminum alloy liner is closed to form a seal head, and a bottle opening; the length of the liner of the ultrahigh-pressure gas cylinder is less than 5m, the nominal outer diameter of the straight cylinder section is phi 406-phi 850mm, and the rated pressure of the ultrahigh-pressure gas cylinder is 35-70 Mpa.

Preferably, the wall thickness of the straight cylinder section is 1-10mm, and the integral straightness of the straight cylinder section is not more than 0.5 mm/m;

preferably, the tolerance of the wall thickness of the straight cylinder section is less than or equal to +/-0.1 mm;

preferably, the local straightness at any straight section position of the straight cylinder section is not more than 0.3mm/300 mm;

still preferably, the whole straightness of the straight cylinder section is not more than 1 mm/full length;

still preferably, the roundness of any position of the straight cylinder section is not more than 0.3 mm;

still preferably, the roughness of the inner surface of the straight cylinder section is less than Ra0.8 μm, and the roughness of the outer surface of the straight cylinder section is less than Ra3.2 μm.

Preferably, the structure type of the end enclosure is an ellipsoidal end enclosure, a disc-shaped end enclosure or a hemispherical end enclosure, the structure type of the back enclosure is the same as that of the end enclosure, the thickness of the end enclosure is uniformly and gradually thickened from the edge to the bottle opening, and the thickness of the back enclosure is uniformly and gradually thickened from the edge to the center of the back enclosure;

preferably, the thickness of the end socket is uniformly and gradually thickened from 5-8mm of the edge to 10-15mm of the bottle mouth part;

still preferably, the thickness of the back cover is uniformly and gradually thickened from 5-8mm of the edge to 10-20mm of the center of the back cover.

The manufacturing method of the ultrahigh-pressure gas cylinder liner preferably comprises the following steps:

s1, performing spinning forming on the back cover;

s2, preparing an aluminum alloy inner container spinning pipe;

s3, inspecting and repairing the defects of the aluminum alloy liner cyclone tube, performing visual automatic comparison inspection on the back cover and the straight tube section of the aluminum alloy liner cyclone tube prepared in the step S2 for defects, and repairing the inspected repairable defects;

s4, spinning and forming the end socket and the bottle mouth;

s5, processing a central hole of the bottle mouth;

s6, curved surface flaw detection;

s7, grinding the inner surface of the curved surface;

s8, heat treatment;

s9, cleaning the inner container;

s10, inspecting the finished product;

s11, coating, namely coating a bonding agent on the outer surface of the ultrahigh-pressure gas cylinder liner obtained in the step S10 to obtain an aluminum alloy liner coating piece;

and S12, winding the carbon fiber on the aluminum alloy inner container coating piece obtained in the step S11, and after the winding is finished, precisely processing the inner diameter, the outer diameter, the inner thread and the outer thread of the bottle mouth.

In the above method for manufacturing an inner container of an ultrahigh-pressure gas cylinder, preferably, the step S1 specifically includes: carrying out multi-pass heating common spinning or deep-drawing spinning on a round or square plate blank by adopting common spinning equipment to prepare a seamless pipe consisting of a sealed bottom and a straight barrel section with an opening at one end; the common spinning equipment is a single-wheel numerical control common spinning machine or a double-spinning-wheel numerical control common spinning machine with a mirror image function; the spinning method is single-spinning wheel multi-pass common spinning or double-spinning wheel multi-pass mirror image common spinning; during spinning, a die with the end part shape being the same as the shape of the inner surface of the sealing bottom of the ultrahigh-pressure gas cylinder liner is adopted for auxiliary processing, and the length of the die is 1.2-1.5 times of that of the seamless pipe;

preferably, the tail end of the die is provided with a discharging device which can automatically discharge;

preferably, the common spinning equipment is a double-spinning-wheel numerical control common spinning machine with a mirror image function.

In the above method for manufacturing an inner container of an ultrahigh-pressure gas cylinder, preferably, the step S1 specifically includes the following steps:

s1a, heating the plate blank, and heating the part of the plate blank to be spun to 200-400 ℃;

s1b, performing bottom sealing, namely performing bottom sealing performing processing on the plate blank heated in the step S1a by adopting 1-3-pass double-spinning-wheel multi-pass mirror image common spinning, wherein the spinning process is performed without being attached to a die, and the heating is continuously carried out in the spinning process, so that the spinning piece is kept at 200-400 ℃;

s1c, sealing and forming, namely performing 3-5-pass double-spinning-wheel multi-pass mirror image composite spinning on the preformed piece prepared in the step S1b by adopting a thickness-gradient spinning method to obtain a sealed formed piece, and continuously heating in the spinning process to keep the spun piece at 200-400 ℃;

s1d, performing the straight cylinder section on the part to be spun of the back cover formed piece prepared in the step S1c by adopting 6-10-pass double-spinning-wheel multi-pass mirror image composite spinning, thus preparing the seamless pipe material consisting of the back cover and the straight cylinder section with an opening at one end, and continuously heating in the spinning process to keep the spinning piece at 200-;

preferably, in step S1c and step S1d, a reverse spinning process of 4-8 times is performed while the double-spinning wheel multi-pass mirror image common spinning is performed for thickening the blank of the straight-tube section to be processed;

still preferably, the heating in said steps S1a-S1d is combustion flame heating with oxygen, propane/L NG.

In the above method for manufacturing an ultra-high pressure gas cylinder liner, preferably, step S2 includes: performing multi-pass powerful external spinning forming treatment on the straight cylinder section of the seamless pipe manufactured in the step S1 by adopting a numerical control powerful external spinning machine to obtain an aluminum alloy inner container spinning pipe; the method specifically comprises the following steps:

s21, spinning and forming the straight cylinder section of the aluminum alloy inner container spinning pipe, and performing 2-4 times of spinning processes on the straight cylinder section of the seamless pipe manufactured in the step S1 by adopting a three-wheel offset forward spinning method to obtain a spinning piece A; during spinning, a core mold with the processing length equal to 1.2-1.4 times of the length of a set product is adopted for spinning auxiliary processing;

s22, processing the spinning pipe of the aluminum alloy liner in a fixed length mode, and processing the spinning piece A obtained in the step S21 in a fixed length mode through a sawing machine to obtain the spinning pipe of the aluminum alloy liner;

s23, cleaning the aluminum alloy inner container spinning pipe, and cleaning the aluminum alloy inner container spinning pipe obtained in the step S22 by using a cleaning machine;

s24, performing flaw detection on the aluminum alloy inner container spinning tube, performing full-automatic flaw detection on the bottom sealing and straight cylinder section of the aluminum alloy inner container spinning tube obtained in the step S23 by adopting a curved surface ultrasonic automatic flaw detector, and detecting whether the machining defects of peeling, wrinkling and cracks exist or not;

preferably, the offset amount in the three-wheel offset forward spinning method in the step S21 is set to 6-12 mm;

preferably, the cleaning machine in the step S23 is a rotary spray cleaning machine or an ultrasonic cleaning machine;

preferably, the cleaning of the aluminum alloy inner container spinning pipe with one end sealed is completed by a neutral cleaning agent heated to 30-45 ℃;

preferably, the residual water stain on the surface of the aluminum alloy inner container spinning tube with the bottom sealed at one end is removed by a wiping tool or a drying device after the aluminum alloy inner container spinning tube with the bottom sealed at one end is cleaned.

In the above method for manufacturing an ultra-high pressure gas cylinder liner, preferably, step S4 includes: and (4) carrying out spin forming of the end socket and the bottle mouth on the opening of the aluminum alloy liner spin-pressing pipe repaired in the step S3 by adopting a heating closing-up spinning machine to obtain a spin-formed part B, and specifically comprising the following steps:

s41, clamping, namely clamping the spinning pipe of the aluminum alloy liner by adopting the split hollow main shaft;

s42, heating, namely heating the spinning part to be closed of the spinning pipe of the aluminum alloy liner to 200-400 ℃;

s43, forming and spinning the end socket and the bottle mouth, and performing multi-pass closing-up spinning on the aluminum alloy liner spinning tube heated in the step S42 by adopting a single-side X-line, Z-line and rotary three-way interpolation type closing-up spinning machine to obtain a spinning forming piece B;

preferably, the heating in step S42 is combustion flame heating using oxygen, propane/L NG.

In the above method for manufacturing an ultrahigh-pressure gas cylinder liner, preferably, the method for manufacturing an ultrahigh-pressure gas cylinder liner includes:

s5, processing a center hole of the bottle mouth, namely, processing the center hole of the bottle mouth of the spinning formed piece B obtained in the step S4 by a machine to obtain a spinning formed piece C;

s6, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S5, and detecting whether the position of a seal head has machining defects of orange peel and folding;

s7, grinding the inner surface of the curved surface, and grinding the defects of the inner surface of the end socket found in the step S6 by using an end socket inner surface grinding machine tool according to the flaw detection result to obtain a spinning formed part C with qualified quality;

s8, performing heat treatment, namely performing T6 process treatment on the spinning forming piece C obtained in the step S7 to obtain an ultrahigh-pressure gas cylinder liner blank;

s9, cleaning the inner container, namely performing high-pressure water spraying cleaning on the inner cavity of the ultrahigh-pressure gas cylinder inner container obtained in the step S8 by using a vertical gas cylinder inner container cleaning machine to remove aluminum scraps and other processing pollutants;

preferably, the step S7 specifically includes the following steps:

s71, clamping the spinning forming piece C by adopting a clamping tool;

s72, automatically observing and judging the defect condition of the inner surface of the end socket by using an automatic endoscope system arranged on the end socket inner surface grinding machine tool, recording the corresponding position, and combining artificial confirmation;

s73, grinding the defects of the inner surface of the end socket found in the step S6 by using an inner surface grinding mechanism of the end socket of the inner surface grinding machine tool of the end socket to obtain a spinning formed part C with qualified quality;

preferably, the clamping tool for the spinning forming part C is a split type hollow clamping tool;

preferably, the grinding of the inner profile of the end socket is a numerical control automatic grinding mechanism which can be programmed and executed independently.

In the above method for manufacturing an ultra-high pressure gas cylinder liner, preferably, the step S8 includes the steps of:

s81, quenching, namely putting the spinning formed part C prepared in the step S7 into a quenching furnace for quenching, heating the spinning formed part C to 525-531 ℃, preserving heat for 2-4 hours in the environment of 525-531 ℃, and then quenching the spinning formed part C;

s82, aging treatment, namely transferring the quenched spinning formed part C to an aging furnace for aging treatment, and finally preserving heat for 6-10 hours in an environment of 160-200 ℃ to obtain an ultrahigh-pressure gas cylinder liner blank;

preferably, the quenching furnace is a vertical aluminum alloy box-type quenching furnace;

still preferably, the aging furnace is a trolley type aluminum alloy aging furnace.

Compared with the closest prior art, the technical scheme provided by the invention has the following beneficial effects:

the manufacturing method of the ultrahigh-pressure gas cylinder liner provided by the invention adopts the plate blank as a raw material, and the spinning processing method is adopted overall, so that the product processing precision is high, the whole body has no welding line, the surface quality is strictly controlled, and the requirement of the ultrahigh-pressure gas cylinder liner is met. And the preparation process is simple, the operation is convenient, the energy consumption is low, the pollution is small, the loss of raw materials in the whole preparation process is less, and the raw material cost is saved. The nominal outer diameter of the ultrahigh-pressure gas cylinder liner processed by the manufacturing method is phi 406-phi 850mm, and the volume and the pressure which can be borne after winding are far higher than those of the existing standard aluminum alloy liner; the wall thickness of the straight cylinder section is 1-10mm, and the straight cylinder section has the characteristics of thin wall and light weight; the tensile strength of the straight cylinder section is more than or equal to 345MPa, the yield strength is more than or equal to 310MPa, and the elongation is more than or equal to 15 percent; the grain size of the texture at any position of the straight cylinder section is more than or equal to 6 grades according to the standard of ASTME112, the texture of the material in the straight cylinder section is uniform and compact, the overall strength effect is excellent, and the straight cylinder section has the characteristic of high pressure resistance.

The method creatively carries out visual automatic comparison and inspection on the defects after the aluminum alloy inner container spinning tube is prepared, repairs the repairable defects, ensures that the prepared aluminum alloy inner container has no surface defects with the depth of more than 0.03mm at any position, ensures that the smoothness of the inner surface of the aluminum alloy inner container reaches Ra0.8 mu m after the repair, and ensures that the prepared gas cylinder has the rated pressure of 35-70MPa of ultrahigh pressure by timely carrying out surface quality repair on a semi-finished product in the preparation step, thereby having important significance for the preparation of the ultrahigh-pressure gas cylinder.

Drawings

FIG. 1 is a schematic structural diagram of an inner container of an ultrahigh-pressure gas cylinder in an embodiment of the invention;

fig. 2 is a flow chart of a manufacturing method of the liner of the ultrahigh-pressure gas cylinder in the embodiment of the invention.

In the figure: 1. sealing the bottom; 2. a straight cylinder section; 3. sealing the end; 4. and (5) opening the bottle.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.

The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, the terms "connected" and "connected" used in the present invention should be interpreted broadly, for example, as a fixed connection or a detachable connection; they may be directly connected or indirectly connected through intermediate members, and specific meanings of the above terms will be understood by those skilled in the art as appropriate.

The invention provides a method for manufacturing an ultrahigh-pressure gas cylinder liner, wherein the ultrahigh-pressure gas cylinder liner is formed by processing a round or square plate blank by the manufacturing method; as shown in fig. 1, the ultra-high pressure gas cylinder liner is an aluminum alloy liner with an integrated seamless structure, wherein one end of the aluminum alloy liner is sealed by a back cover 1, the other end of the aluminum alloy liner is sealed by a formed end socket 3 and a bottle opening 4, the aluminum alloy liner comprises the back cover 1, a straight cylinder section 2, the end socket 3 and the bottle opening 4, the back cover 1 and the end socket 3 are respectively arranged at two ends of the straight cylinder section 2, and the bottle opening 4 is arranged on the end. The structure type of the end socket 3 is an ellipsoidal end socket 3, a disc-shaped end socket 3 or a hemispherical end socket 3, the structure type of the back cover 1 is the same as that of the end socket 3, and in the embodiment of the invention, the structure types of the back cover 1 and the end socket 3 are ellipsoidal; the length of the aluminum alloy inner container of the ultrahigh-pressure gas cylinder is less than 5m, the nominal outer diameter of the straight cylinder section 2 is phi 406-phi 850mm, the wall thickness of the straight cylinder section 2 is 1-10mm (such as 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm and 10mm), and the integral straightness of the straight cylinder section 2 is not more than 0.5 mm/m; the tolerance of the wall thickness of the straight cylinder section 2 is less than or equal to +/-0.1 mm; the local straightness at any straight section position of the straight cylinder section 2 is not more than 0.3mm/300 mm; the integral straightness of the straight cylinder section 2 is not more than 1 mm/full length; the roundness of any position of the straight cylinder section 2 is not more than 0.3 mm; the roughness of the inner surface of the straight cylinder section 2 is less than Ra0.8 μm, and the roughness of the outer surface of the straight cylinder section 2 is less than Ra3.2 μm. The thickness of the seal head 3 is uniformly gradually thickened from the edge to the bottle mouth 4, and the thickness of the back cover 1 is uniformly gradually thickened from the edge to the center of the back cover 1; the thickness of the seal head 3 is uniformly and gradually increased from 5-8mm (such as 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, 7.3mm, 7.6mm and 7.8mm) of the edge to 10-15mm (such as 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm, 13mm, 13.5mm, 14mm, 14.5mm and 15mm) of the position of the bottle mouth 4; the thickness of the back cover 1 is uniformly gradually thickened from 5-8mm (such as 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, 7.3mm, 7.6mm and 7.8mm) of the edge to 10-20mm (such as 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 6mm, 17mm, 8mm, 9mm and 20mm) of the center of the back cover 1; the rated pressure of the ultrahigh-pressure gas cylinder is 35-70MPa (such as 36MPa, 39MPa, 42MPa, 45MPa, 48MPa, 51MPa, 54MPa, 57MPa, 60MPa, 63MPa, 66MPa, and 69 MPa).

As shown in fig. 2, the method for manufacturing the liner of the ultrahigh-pressure gas cylinder comprises the following steps:

s1, performing spinning forming on the back cover 1, and performing multi-pass heating common spinning or deep drawing spinning on a round or square plate blank by using common spinning equipment to obtain the seamless pipe consisting of the back cover 1 and the straight barrel section 2 with an opening at one end. The common spinning equipment is a single-wheel numerical control common spinning machine or a double-spinning-wheel numerical control common spinning machine with a mirror image function; the spinning method is single-spinning wheel multi-pass common spinning or double-spinning wheel multi-pass mirror image common spinning; the end part of the mould is processed by adopting a mould with the same shape as the inner surface shape of the back cover 1 of the ultrahigh-pressure gas cylinder liner during spinning, and the length of the mould is 1.2 to 1.5 times (such as 1.23 times, 1.26 times, 1.29 times, 1.32 times, 1.35 times, 1.38 times, 1.41 times, 1.44 times, 1.47 times and 1.49 times) of the length of the seamless pipe; in order to facilitate the quick unloading of the spun seamless steel tube, the tail end of the die is provided with an unloading device which can automatically unload materials; in the embodiment of the invention, a double-spinning-wheel numerical control common spinning machine with a mirror image function is adopted to carry out double-spinning-wheel multi-pass mirror image common spinning on the plate blank so as to prepare the seamless pipe. A plate blank with a thickness of 20-25mm (such as 20.5mm, 21mm, 21.5mm, 22mm, 22.5mm, 23mm, 23.5mm, 24mm, 24.5mm, 25mm) is selected as a spinning blank. The method specifically comprises the following steps:

s1a, heating the plate blank, heating the part to be spun of the plate blank to 400 ℃ (such as 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃) by adopting oxygen and propane/L NG;

s1b, performing the sealing bottom 1, programming the whole spinning track by using a graph, performing the pre-forming processing of the sealing bottom 1 on the plate blank heated in the step S1a by adopting 1-3-pass double-spinning wheel multi-pass mirror image common spinning, wherein the spinning process is performed without being attached to a die, and the heating is continuously carried out in the spinning process, so that the spinning piece is kept at 200 ℃ and 400 ℃ (for example, 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃);

s1c, molding the back cover 1, performing 3-5-pass double-spinning wheel multi-pass mirror image composite spinning on the preformed piece prepared in the step S1b by adopting a thickness-gradient spinning method to obtain a molded piece of the back cover 1, and continuously heating in the spinning process to keep the temperature of the spun piece at 200-400 ℃ (such as 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃);

s1d, pre-forming the straight cylinder section 2 on the part to be spun of the formed piece of the back cover 1 obtained in the step S1c by adopting double-rotation wheel multi-pass mirror image composite spinning of 6-10 passes (such as 6 passes, 7 passes, 8 passes, 9 passes and 10 passes) so as to obtain a seamless pipe material consisting of the back cover 1 and the straight cylinder section 2 with one open end, and continuously heating to keep the spun piece at 200-400 ℃ (such as 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃) in the spinning process.

In step S1c and step S1d, a 4-8 times derotation process is inserted while the double-spinning wheel multi-pass mirror image normal spinning is used for thickening the blank of the straight-tube section 2 to be processed. The total number of spinning passes in the whole spinning process is 10-18 (for example, 10, 11, 12, 13, 14, 15, 16, 17 and 18), and the length of the straight section 2 of the prepared seamless pipe is not more than 1.7 m; the thickness of the back cover 1 is uniformly and gradually thickened from 5-8mm of the edge to 10-20mm, such as 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 6mm, 17mm, 8mm, 9mm and 20mm) of the center of the back cover 1.

S2, preparing the aluminum alloy inner container spinning tube, and performing multi-pass spinning forming treatment on the straight tube section 2 of the seamless tube material prepared in the step S1 by adopting common spinning equipment in the step S1 or additionally adopting a numerical control spinning machine, so as to obtain the aluminum alloy inner container spinning tube; the method specifically comprises the following steps:

s21, spinning and forming the straight tube section 2 of the aluminum alloy liner spinning tube, and spinning the seamless tube material prepared in the step S1 for 2-4 times (for example, 2 times, 3 times and 4 times) by a two-wheel/three-wheel offset forward spinning method by using a two-wheel/three-wheel powerful numerical control spinning machine to obtain a spinning piece A; the spinning is carried out by using a core die with the processing length equal to 1.2-1.4 times (such as 1.23 times, 1.26 times, 1.29 times, 1.32 times, 1.35 times and 1.38 times) of the set product length, and the offset amount in the two-wheel/three-wheel offset forward spinning method is set to be 6-12mm (such as 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, 10.5mm, 11mm and 11.5 mm); the total deformation of the seamless pipe after spinning treatment is 55-70%. The spinning piece A is a straight cylinder with the same thickness of one end sealing bottom 1 or a straight cylinder section 2 with one end sealing bottom 1 and one end provided with an outer annular end frame.

S22, processing the spinning pipe of the aluminum alloy liner in a fixed length mode, and processing the spinning piece A obtained in the step S21 in a fixed length mode through a sawing machine to obtain the spinning pipe of the aluminum alloy liner; in the embodiment of the invention, the sawing machine adopts a double-column automatic sawing machine, and the saw blade adopts a special aluminum alloy saw blade.

S23, cleaning the aluminum alloy inner container spinning tube, and cleaning the aluminum alloy inner container spinning tube obtained in the step S22 by adding a neutral cleaning agent at 30-45 ℃ into a rotary spray cleaning machine or an ultrasonic cleaning machine; after cleaning, removing residual water stains on the surface by using a special wiping tool or a drying device;

s24, performing flaw detection on the aluminum alloy inner container spinning tube, performing full-automatic flaw detection on the bottom sealing 1 and the straight cylinder section 2 of the aluminum alloy inner container spinning tube obtained in the step S23 by adopting a special curved surface ultrasonic automatic flaw detector, and detecting whether machining defects such as peeling, wrinkles, cracks and the like exist or not;

s3, defect inspection and repair are carried out on the aluminum alloy liner spin-pressure pipe, visual automatic comparison inspection of defects is carried out on the back cover 1 and the straight cylinder section 2 of the aluminum alloy liner spin-pressure pipe obtained in the step S2, and the inspected defects are repaired; the method specifically comprises the following steps:

s31, detecting defects of the back cover 1 and the straight cylinder section 2, performing visual automatic comparison detection on the back cover 1 and the straight cylinder section 2 of the aluminum alloy liner spinning tube obtained in the step S2 on an intelligent inner and outer circle grinding machine tool through an integrated visual detection system, detecting scratches and collisions with the depth of the inner surface larger than 0.03mm, and detecting defects such as air holes, inclusions, pits, microcracks and the like;

s32, automatically repairing the repairable scratch and the defect detected in the step S31 by adopting an automatic internal grinding machine tool; the method specifically comprises the following steps:

s321, grinding the outer surface of the aluminum alloy inner container spinning tube by using a cloth abrasive belt;

s322, roughly grinding the inner surface of the aluminum alloy inner container spinning tube by using a millennium grinding wheel;

and S323, carrying out fine grinding on the inner surface of the aluminum alloy inner container spinning tube by using a scouring pad wheel.

S4, spinning and forming the end socket 3 and the bottle mouth 4, wherein the end socket 3 and the bottle mouth 4 are spun and formed at the opening of the aluminum alloy liner spinning pipe by adopting a heating closing spinning machine to obtain a spinning and forming piece B; the method specifically comprises the following steps:

s42, carrying out flame spraying and heating on the spinning part to be closed of the spinning pipe of the aluminum alloy liner to 400 ℃ (such as 220 ℃, 240 ℃, 260 ℃, 280 ℃, 300 ℃, 320 ℃, 340 ℃, 360 ℃ and 380 ℃) by adopting oxygen and propane/L NG combustion;

s43, forming and spinning the end socket 3 and the bottle mouth 4, and performing closing-in spinning on the aluminum alloy liner spinning tube heated in the step S42 for 10-18 passes (such as 10 passes, 11 passes, 12 passes, 13 passes, 14 passes, 15 passes, 16 passes, 17 passes and 18 passes) by adopting a one-side X-line, Z-line and rotary three-way interpolation type closing-in spinning machine to obtain a spinning formed piece B; in the spinning process, the closing spinning is carried out in the 1 st to 8 th passes (such as 1 pass, 2 passes, 3 passes, 4 passes, 5 passes, 6 passes, 7 passes and 8 passes) with reverse spinning, and is used for thickening the 4 parts of the bottle mouth; the thickness of the end socket 3 of the prepared spinning forming piece B is uniformly and gradually thickened from 5-8mm (such as 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, 7.3mm, 7.6mm and 7.8mm) of the edge to 10-15mm (such as 10.5mm, 11mm, 11.5mm, 12mm, 12.5mm, 13mm, 13.5mm, 14mm and 14.5mm) of the position of the bottle mouth 4;

s5, processing a central hole of the bottle mouth 4, and clamping a spinning formed part B by adopting a split type hollow clamping tool; machining a center hole of the bottle opening 4 of the spinning forming piece B obtained in the step S3 by using a special bottle opening 4 machining center to obtain a spinning forming piece C; ready for subsequent T6 processing;

s6, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S4 by adopting a special curved surface ultrasonic automatic flaw detector, and detecting whether machining defects such as orange peel and folding exist at the position of the end socket 3;

s61, clamping the spinning forming piece C by adopting a split type hollow clamping tool;

and S62, performing full-automatic flaw detection on the closing quality of the end socket 3 and the opening 4 of the spinning forming piece C obtained in the step S5 by using a special curved surface ultrasonic automatic flaw detector, and detecting whether the position of the end socket 3 has machining defects such as orange peel and folding.

S7, grinding the inner surface of the curved surface, and grinding the inner surface defects of the end socket 3 found in the step S6 by adopting a special end socket 3 inner surface grinding machine tool according to the flaw detection result to obtain a spinning formed part C with qualified quality; the method specifically comprises the following steps:

s71, clamping the spinning forming piece C by adopting a split type hollow clamping tool;

s72, automatically observing and judging the defect condition of the inner surface of the end socket 3 by using an automatic endoscope system of the special end socket 3 inner surface grinding machine tool, recording the corresponding position, and combining artificial confirmation;

and S73, grinding the defects of the inner surface of the end socket 3 found in the step S6 by adopting a numerical control automatic grinding mechanism of the special end socket 3 inner surface grinding machine tool to obtain a spinning formed part C with qualified quality, wherein the numerical control automatic grinding mechanism can be programmed and independently executed in the grinding process.

S8, performing heat treatment, namely performing T6 process treatment on the spinning forming piece C obtained in the step S7 to obtain an ultrahigh-pressure gas cylinder liner blank; the method specifically comprises the following steps:

s81, a quenching treatment, in which the spin-formed article C obtained in the step S7 is put into a vertical aluminum alloy box type quenching furnace to be quenched, the spin-formed article C is heated to 525-;

s82, aging treatment, transferring the quenched spinning formed piece C to a trolley type aluminum alloy aging furnace for aging treatment, and finally preserving heat for 6-10 hours (such as 6.3 hours, 6.6 hours, 7 hours, 7.3 hours, 7.7 hours, 8 hours, 8.4 hours, 8.7 hours, 9 hours, 9.3 hours and 9.7 hours) in an environment of 160-200 ℃ (such as 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃ and 198 ℃) to prepare the ultrahigh-pressure gas cylinder liner blank. In the whole quenching treatment and aging treatment processes, the ultrahigh-pressure gas cylinder liner blank is vertically fixed in a special heat treatment material frame by adopting a special heat treatment tool, and in the treatment process, one section of the back cover 1 is upwards placed.

S9, cleaning the inner container, namely performing high-pressure water spraying cleaning on the inner cavity of the inner container of the ultrahigh-pressure gas cylinder obtained in the step S8 by using a special vertical gas cylinder inner container cleaning machine to remove aluminum scraps and other processing pollutants; the method specifically comprises the following steps:

s91, vertically placing the ultrahigh-pressure gas cylinder liner on a special vertical gas cylinder liner cleaning machine with a downward bottle opening 4, enabling a spraying mechanism of the special vertical gas cylinder liner cleaning machine to enter the liner, and fixing the liner;

and S92, cleaning the inner cavity of the ultrahigh-pressure gas cylinder liner by adopting a high-pressure water spraying or ultrasonic cleaning mode to remove aluminum scraps and other processing pollutants.

And S10, inspecting the finished product, namely inspecting the ultrahigh-pressure gas cylinder liner obtained in the step S9 to obtain the finished product of the ultrahigh-pressure gas cylinder liner.

And S11, coating, namely coating a bonding agent on the outer surface of the ultrahigh-pressure gas cylinder liner obtained in the step S10 to obtain an aluminum alloy liner coating piece so as to improve the bonding degree between the aluminum alloy and the resin and the fibers to be wound.

S12, carbon fiber winding is carried out on the aluminum alloy inner container coating piece obtained in the step S11, precision machining of the inner diameter and the outer diameter of the bottle opening 4 and the inner thread and the outer thread is carried out after the winding is finished, so that the molded surface of the bottle opening 4 is prevented from being oxidized and damaged in the heat treatment process and other processes, the machined surface meets the requirements of ultrahigh precision and finish degree, the requirement for hydrogen micromolecule ultrahigh sealing is met, the ultrahigh-pressure gas bottle with one end sealed at the bottom 1 is obtained, the limit pressure-bearing condition of the ultrahigh-pressure gas bottle is detected, the length of the bottle opening 4 is 40mm, the outer diameter of the bottle opening 4 is 50mm, and the inner.

The length of the ultrahigh-pressure gas cylinder liner prepared by the manufacturing method is less than 5m, the nominal outer diameter of the straight cylinder section 2 is phi 406-phi 850mm, the wall thickness of the straight cylinder section 2 is 1-10mm, and the integral straightness of the straight cylinder section 2 is not more than 1 mm/full length; the tolerance of the wall thickness of the straight cylinder section 2 is less than or equal to +/-0.1 mm; the local straightness at any straight section position of the straight cylinder section 2 is not more than 0.3mm/300 mm; the roundness of any position of the straight cylinder section 2 is not more than 0.3 mm; the roughness of the inner surface of the straight cylinder section 2 is less than Ra0.8 μm, and the roughness of the outer surface of the straight cylinder section 2 is less than Ra3.2 μm. The volume of the ultrahigh-pressure gas cylinder liner prepared by the manufacturing method is far higher than that of the existing standard aluminum alloy liner, and the ultrahigh-pressure gas cylinder liner also has the characteristics of high reliability, thin wall thickness, high pressure resistance, light weight and the like.

Example 1

The method for preparing the ultrahigh-pressure gas cylinder liner with the diameter of 500mm, the length of 3.5m and the wall thickness of 5mm has the requirement of the rated pressure of an ultrahigh-pressure gas cylinder of 70MPa, and specifically comprises the following operation steps:

s1, spin forming the back cover 1

Selecting a plate blank with the thickness of 20mm and the diameter of phi 1200mm as a spinning blank, firstly heating the plate blank to be spun to 360 ℃, writing a spinning program according to the following parameters, and carrying out common spinning:

firstly, carrying out 3-pass double-spinning-wheel multi-pass mirror image common spinning for preforming spinning, wherein the spinning process is non-attaching die spinning;

then, forming and spinning the 1 section of the back cover by 3 times, and spinning by adopting a spinning method with gradually changed thickness in the spinning process;

then carrying out the molding of the straight-through cylinder section by the common spinning of the double-spinning wheel multi-pass mirror image of 6 passes;

thereby preparing a seamless pipe material consisting of a back cover 1 and a straight cylinder section 2 with an opening at one end, wherein the diameter of the back cover 1 of the seamless pipe material is 500mm, the thickness of the back cover 1 is uniformly and gradually thickened from 8mm at the edge to 12mm at the center of the back cover 1, the length of the straight cylinder section 2 is 1600mm, and the thickness of the straight cylinder section 2 is 10 mm.

S2, preparing the aluminum alloy inner container spinning tube, which comprises the following steps:

s21, performing pass three-wheel offset forward spinning on the seamless pipe manufactured in the step S1 by adopting a core die with the machining length of 4000mm, wherein the offset is set to be 6 mm;

obtaining a spinning piece A; the dimensions of the spinning piece A are as follows: the length of the straight cylinder section 2 is 3600mm, and the thickness of the straight cylinder section 2 is 5 mm.

S22, performing fixed-length processing on the spinning piece A obtained in the step S21 by using a sawing machine to obtain the aluminum alloy liner spinning tube, wherein the length of the straight tube section 2 of the aluminum alloy liner spinning tube is 3500 mm;

s23, cleaning the aluminum alloy inner container spinning tube, and cleaning the aluminum alloy inner container spinning tube obtained in the step S22 by adding a 40 ℃ neutral cleaning agent into a rotary spray cleaning machine or an ultrasonic cleaning machine; after cleaning, removing residual water stains on the surface by using a special wiping tool or a drying device;

s3, visual inspection and repair of the aluminum alloy liner spinning tube, wherein the back cover 1 and the straight cylinder section 2 of the aluminum alloy liner spinning tube obtained in the step S2 are subjected to visual automatic comparison inspection, and the inspected defects are repaired; the method specifically comprises the following steps:

s31, visually inspecting the back cover 1 and the straight cylinder section 2, and performing visual automatic comparison inspection on the back cover 1 and the straight cylinder section 2 of the aluminum alloy liner spinning tube obtained in the step S2 on an intelligent internal and external grinding machine tool through an integrated visual inspection system, inspecting scratches and bumps of the inner surface with the depth larger than 0.03mm, and inspecting defects such as air holes, inclusions, pits, microcracks and the like;

s32, automatically repairing the repairable defects detected in the step S31 by adopting an automatic inner circle grinding machine tool; the method specifically comprises the following steps:

s41, clamping the aluminum alloy liner spinning tube by adopting the split hollow main shaft;

s42, carrying out flame spraying and heating on the spinning position to be closed of the spinning pipe of the aluminum alloy liner to 360 ℃ by adopting oxygen and propane/L NG combustion;

s43, performing closing-up spinning on the aluminum alloy liner spinning tube by adopting a unilateral X-linear, Z-linear and rotary three-way interpolation type closing-up spinning machine to obtain a spinning forming piece B;

in the spinning process, the closing spinning band has 4 times of reverse spinning and is used for thickening 4 parts of the bottle mouth; the thickness of the end socket 3 of the prepared spinning forming part B is uniformly and gradually thickened from 8mm at the edge to 12mm at the position of the bottle mouth 4.

S5, processing a central hole of the bottle mouth 4, and clamping a spinning formed part B by adopting a split type hollow clamping tool; machining a center hole of the bottle opening 4 of the spinning forming piece B obtained in the step S4 by using a special bottle opening 4 machining center to obtain a spinning forming piece C; ready for subsequent T6 processing;

s6, performing curved surface flaw detection, performing closing quality flaw detection on the spinning formed part C obtained in the step S5 by adopting a special curved surface ultrasonic automatic flaw detector, and detecting whether machining defects such as orange peel and folding exist at the position of the end socket 3;

and S73, grinding the defects of the inner surface of the end socket 3 found in the step S5 by adopting a numerical control automatic grinding mechanism of the special end socket 3 inner surface grinding machine tool to obtain a spinning formed part C with qualified quality, wherein the numerical control automatic grinding mechanism can be programmed and independently executed in the grinding process.

s81, quenching, namely putting the spinning formed part C prepared in the step S7 into a vertical aluminum alloy box type quenching furnace for quenching, heating the spinning formed part C to 525-;

and S82, aging, transferring the quenched spinning formed piece C to a trolley type aluminum alloy aging furnace for aging, and finally preserving heat for 10 hours in an environment of 170 ℃ to obtain the ultrahigh-pressure gas cylinder liner blank. In the whole quenching treatment and aging treatment processes, the ultrahigh-pressure gas cylinder liner blank is vertically fixed in a special heat treatment material frame by adopting a special heat treatment tool, and in the treatment process, one section of the back cover 1 is upwards placed.

And S10, inspecting the finished product, namely inspecting the ultrahigh-pressure gas cylinder liner obtained in the step S9, performing sampling inspection on part of items, measuring the texture grain sizes of any six positions of the ultrahigh-pressure gas cylinder liner subjected to sampling inspection, and respectively setting the texture grain sizes of the six positions to be 8-grade, 6-grade, 7-grade and 7-grade according to the ASTME112 standard according to the measurement result, and inspecting the tensile strength of the straight cylinder section 2 of the ultrahigh-pressure gas cylinder liner subjected to sampling inspection. And (3) respectively measuring the yield strength and the elongation, wherein the tensile strength of the straight cylinder section 2 is 345MPa, the yield strength is 310MPa and the elongation is 15 percent through measurement, and the products produced in the batch are qualified to obtain the finished product of the ultrahigh-pressure gas cylinder liner.

S12, carbon fiber winding is carried out on the aluminum alloy inner container coating piece obtained in the step S11, precision machining of the inner thread and the outer thread of the bottle opening 4 is carried out after the winding is finished, so that the molded surface of the bottle opening 4 is prevented from being oxidized and damaged in the processes of heat treatment and the like, the machined surface meets the requirements of ultrahigh precision and smoothness, the requirement of hydrogen for small molecule ultrahigh sealing is met, the ultrahigh-pressure gas bottle with one end sealed at the bottom 1 is obtained, the limit pressure-bearing condition of the ultrahigh-pressure gas bottle is detected, the length of the bottle opening 4 is 40mm, the outer diameter of the bottle opening 4 is 50mm, and the inner diameter of the.

Through inspection, the texture grain size of any position of the liner of the ultrahigh-pressure gas cylinder prepared by the embodiment is more than or equal to 6 levels according to the standard grade of ASTM E112, the tensile strength of the straight cylinder section 2 is 345MPa, the yield strength is 310MPa, and the elongation is 15%; the ultra-high pressure gas cylinder obtained after winding the inner container has the test limit pressure of 150Mpa, and meets the requirement of the rated pressure of 70 Mpa.

Example 2

The method for preparing the liner of the ultrahigh-pressure gas cylinder with the diameter of 650mm, the length of 4m and the wall thickness of 6mm has the rated pressure requirement of 50Mpa, and specifically comprises the following operation steps:

s1, spin forming the back cover 1

Selecting a plate blank with the thickness of 25mm and the diameter of phi 1500mm as a spinning blank, firstly heating the plate blank to be spun to 360 ℃, writing a spinning program according to the following parameters, and carrying out common spinning:

thereby preparing a seamless pipe material consisting of a back cover 1 and a straight cylinder section 2 with an opening at one end, wherein the diameter of the back cover 1 of the seamless pipe material is 620mm, the thickness of the back cover 1 is uniformly and gradually thickened from 8mm at the edge to 12mm at the center of the back cover 1, the length of the straight cylinder section 2 is 2100mm, and the thickness of the straight cylinder section 2 is 12 mm.

s21, performing pass three-wheel offset forward spinning on the seamless pipe manufactured in the step S1 by adopting a core die with the machining length of 5000mm, wherein the offset is set to be 6 mm;

obtaining a spinning piece A; the dimensions of the spinning piece A are as follows: the length of the straight cylinder section 2 is 4200mm, and the thickness of the straight cylinder section 2 is 6 mm.

S22, performing fixed-length processing on the spinning piece A obtained in the step S21 by using a sawing machine to obtain the aluminum alloy liner spinning tube, wherein the length of the straight tube section 2 of the aluminum alloy liner spinning tube is 4000 mm;

And S10, inspecting the finished product, namely inspecting the ultrahigh-pressure gas cylinder liner obtained in the step S9, performing sampling inspection on part of items, measuring the texture grain sizes of any six positions of the ultrahigh-pressure gas cylinder liner subjected to sampling inspection, and respectively setting the texture grain sizes of the six positions to be 8-grade, 7-grade, 6-grade and 7-grade according to the ASTME112 standard according to the measurement result, and inspecting the tensile strength of the straight cylinder section 2 of the ultrahigh-pressure gas cylinder liner subjected to sampling inspection. And (3) respectively measuring the yield strength and the elongation, wherein the tensile strength of the straight cylinder section 2 is 356MPa, the yield strength is 323MPa and the elongation is 17 percent through measurement, and the batch of produced products are qualified to obtain a finished product of the ultrahigh-pressure gas cylinder liner.

Through inspection, the texture grain size of any position of the liner of the ultrahigh-pressure gas cylinder prepared by the embodiment is more than or equal to 6 levels according to the standard grade of ASTM E112, and the straight cylinder section 2 has the tensile strength of 356MPa, the yield strength of 323MPa and the elongation of 17 percent; the ultra-high pressure gas cylinder obtained after winding the inner container has the test limit pressure of 132Mpa, and meets the requirement of 50Mpa of rated pressure.

In conclusion, the manufacturing method of the ultrahigh-pressure gas cylinder liner provided by the invention generally adopts a spinning processing method, so that the energy consumption is low, the pollution is small, the loss of raw materials in the whole manufacturing process is less, and the raw material cost is saved. The nominal external diameter of the ultrahigh-pressure gas cylinder liner processed by the manufacturing method is phi 406-phi 850mm, and the volume and bearing pressure of the ultrahigh-pressure gas cylinder liner are far higher than those of the existing standard aluminum alloy liner; the wall thickness of the straight cylinder section is 1-10mm, and the straight cylinder section has the characteristics of thin wall thickness and light weight; the tensile strength of the straight cylinder section is more than or equal to 345MPa, the yield strength is more than or equal to 310MPa, and the elongation is more than or equal to 15 percent; the grain size of the texture at any position of the straight cylinder section is more than or equal to grade 6 according to the ASTME112 standard, the texture of the material in the straight cylinder section is uniform and compact, the overall strength effect is excellent, and the straight cylinder section has high pressure resistance and has important significance for manufacturing ultrahigh pressure gas cylinders.

The above description is only exemplary of the invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the invention is intended to be covered by the appended claims.

Claims

1. The manufacturing method of the ultrahigh-pressure gas cylinder liner is characterized by comprising the following steps of:

s1, performing rotary forming on the back cover, specifically: carrying out multi-pass heating common spinning or deep-drawing spinning on a round or square plate blank by adopting common spinning equipment to prepare a seamless pipe consisting of a sealed bottom and a straight barrel section with an opening at one end; the common spinning equipment is a single-wheel numerical control common spinning machine or a double-spinning-wheel numerical control common spinning machine with a mirror image function; the spinning method is single-spinning wheel multi-pass common spinning or double-spinning wheel multi-pass mirror image common spinning; during spinning, a die with the end part shape being the same as the shape of the inner surface of the sealing bottom of the ultrahigh-pressure gas cylinder liner is adopted for auxiliary processing, and the length of the die is 1.2-1.5 times of that of the seamless pipe; the thickness of the round or square plate blank is 20-25 mm;

the step S1 specifically includes the following steps:

in the step S1c and the step S1d, a 4-8 times reverse spinning process is inserted while the double-spinning wheel multi-pass mirror image common spinning is performed, and the reverse spinning process is used for thickening the blank of the straight cylinder section to be processed;

s2, preparing an aluminum alloy inner container spinning pipe;

the step S2 is: performing multi-pass powerful external spinning forming treatment on the straight cylinder section of the seamless pipe manufactured in the step S1 by adopting a numerical control powerful external spinning machine to obtain an aluminum alloy inner container spinning pipe; the method specifically comprises the following steps:

the offset in the three-wheel offset forward spinning method in the step S21 is set to be 6-12 mm;

the cleaning machine in the step S23 is a rotary spray cleaning machine or an ultrasonic cleaning machine;

cleaning the aluminum alloy inner container spinning pipe with one end sealed by a neutral cleaning agent heated to 30-45 ℃;

after cleaning the aluminum alloy inner container spinning tube with one end sealed, removing residual water stain on the surface by using a wiping tool or a drying device;

s4, spin forming of the seal head and the bottle mouth: and (4) carrying out spin forming of the end socket and the bottle mouth on the opening of the aluminum alloy liner spin-pressing pipe repaired in the step S3 by adopting a heating closing-up spinning machine to obtain a spin-formed part B, and specifically comprising the following steps:

the closing spinning step 1-8 is provided with reverse spinning and is used for thickening the bottle mouth part;

the thickness of the end socket of the spinning forming piece B is uniformly thickened gradually from 5-8mm of the edge to 10-15mm of the bottle opening;

s5, processing a central hole of the bottle mouth: machining a center hole of the bottle opening of the spinning formed part B obtained in the step S4 to obtain a spinning formed part C;

s6, curved surface flaw detection: performing closing quality flaw detection on the spinning formed part C obtained in the step S5, and detecting whether machining defects of orange peel and folding exist at the end socket position;

s7, grinding the inner surface of the curved surface: grinding the defects of the inner surface of the end socket found in the step S6 by using an end socket inner surface grinding machine tool according to the flaw detection result to obtain a spinning formed part C with qualified quality;

s8, heat treatment: carrying out T6 process treatment on the spinning forming piece C obtained in the step S7 to obtain an ultrahigh-pressure gas cylinder liner blank;

s9, cleaning the inner container: performing high-pressure water spraying cleaning on the inner cavity of the ultrahigh-pressure gas cylinder liner obtained in the step S8 by using a vertical gas cylinder liner cleaning machine to remove aluminum scraps and other processing pollutants;

s10, inspecting the finished product;

s12, winding carbon fibers on the aluminum alloy inner container coating piece obtained in the step S11, and after winding is finished, precisely processing the inner diameter, the outer diameter, the inner thread and the outer thread of the bottle mouth;

the ultrahigh-pressure gas cylinder liner is an integrated seamless aluminum alloy liner with one end being sealed, the other end being closed to form a seal head and a bottle opening, and comprises a bottom seal, a straight cylinder section, a seal head and a bottle opening, wherein the bottom seal and the seal head are respectively positioned at two ends of the straight cylinder section, and the bottle opening is positioned on the seal head; the length of the liner of the ultrahigh-pressure gas cylinder is 3.5-5 m, the nominal outer diameter of the straight cylinder section is phi 500-phi 850mm, and the rated pressure of the ultrahigh-pressure gas cylinder is 36-70 Mpa;

the wall thickness of the straight cylinder section is 1-10mm, and the integral straightness of the straight cylinder section is not more than 0.5 mm/m;

the tolerance of the wall thickness of the straight cylinder section is less than or equal to +/-0.1 mm;

the local straightness at any straight line section position of the straight cylinder section is not more than 0.3mm/300 mm;

the integral straightness of the straight cylinder section is not more than 1 mm/full length;

the roundness of any position of the straight cylinder section is not more than 0.3 mm;

the roughness of the inner surface of the straight cylinder section is less than Ra0.8 mu m, and the roughness of the outer surface of the straight cylinder section is less than Ra3.2 mu m;

the structure type of the end enclosure is an ellipsoidal end enclosure, a disc-shaped end enclosure or a hemispherical end enclosure, the structure type of the bottom enclosure is the same as that of the end enclosure, the thickness of the end enclosure is uniformly and gradually thickened from the edge to the bottle opening, and the thickness of the bottom enclosure is uniformly and gradually thickened from the edge to the center of the bottom enclosure;

the thickness of the seal head is uniformly and gradually thickened from 5-8mm of the edge to 10-15mm of the bottle opening;

the thickness of the back cover is uniformly and gradually thickened from 5-8mm of the edge to 10-20mm of the center of the back cover.

2. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 1, wherein a discharging device is arranged at the tail end of the die and can automatically discharge materials.

3. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 1, wherein the common spinning equipment is a double-spinning-wheel numerical control common spinning machine with a mirror image function.

4. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 1, wherein the heating in the steps S1a-S1d is performed by using oxygen and propane/L NG for combustion flame heating.

5. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 1, wherein the heating in the step S42 is performed by using oxygen and propane/L NG for combustion flame heating.

6. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 1, wherein the step S7 specifically comprises the following steps:

s71, clamping the spinning forming piece C by adopting a clamping tool;

and S73, grinding the defects of the inner surface of the end socket found in the step S6 by using an inner surface grinding mechanism of the end socket of the inner surface grinding machine tool of the end socket to obtain the spinning formed part C with qualified quality.

7. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 6, wherein the clamping tool for the spinning forming part C is a split hollow clamping tool.

8. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 6, wherein the grinding of the inner profile of the seal head is a numerical control automatic grinding mechanism which can be programmed and executed independently.

9. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 6, wherein the step S8 comprises the following steps:

s82, aging treatment, namely transferring the quenched spinning formed part C to an aging furnace for aging treatment, and finally preserving heat for 6-10 hours in an environment of 160-200 ℃ to obtain the ultrahigh-pressure gas cylinder liner blank.

10. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 9, wherein the quenching furnace is a vertical aluminum alloy box-type quenching furnace.

11. The method for manufacturing the liner of the ultrahigh-pressure gas cylinder according to claim 9, wherein the aging furnace is a trolley-type aluminum alloy aging furnace.